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Professor Jerry Coyne has written a post titled, Ken Ham vs. Dawkins: On the nature of science and physical law, in which he criticizes Ken Ham’s claim that evolution is a “historical” science, dealing with events that can’t be observed, and hence can’t be verified. Coyne contends that “there is no distinction between historical science and real-time experimental science: both are based on observation, prediction, and testability.” First, evolution can make predictions about the past which scientists can subsequently verify (e.g. the prediction that “birds evolved from dinosaurs and whales from land-dwelling animals”). It can also make “retrodictions,” by making sense of previously puzzling data: for instance, it can explain “biogeographic patterns like the absence of endemic mammals on oceanic islands, of vestigial organs like the tiny, useless hindlimbs on early fossil whales, and of embryological observations like the transitory hindlimb buds in dolphins.” Moreover, argues Coyne, if Ham were right, and if the historical sciences weren’t observable and testable, then not only evolution but also cosmology, geology and even archaeology would be invalidated as sciences, for all of these sciences deal with events which can’t be observed. Finally, it is incorrect to say that evolution cannot be observed, for we can observe natural selection occurring in real time.
Professor Coyne then proceeds to attack Ham’s claim that atheists have no good reason for expecting there to be any laws of Nature for scientists to discover, or for expecting these to continue holding in the future. In reply, Coyne argues that “God did it” is a poor explanation for the existence of laws, as it is merely a statement of ignorance, and he approvingly quotes Sam Harris’s dictum that “the honest doubts of science are better — and more noble — than the false certainties of religion.” For his part, Coyne finds physicist Sean Carroll’s “That’s just the way it is” a more satisfying and parsimonious explanation than the theistic explanation of the laws of Nature. Coyne also proposes what he calls a “weak anthropic principle from bodies”: “living creatures, at least the type that we see, couldn’t exist without physical law.” Moreover, “[i]f the ‘laws of nature’ were to vary wildly and erratically, we wouldn’t be able to evolve (environments would change unpredictably from one generation to the next), nor would our bodies be able to operate (things like kidney function, nerve function, and blood circulation all depend on ‘laws’ that are constant).” Finally, Coyne notes that religious believers don’t really believe in invariant laws anyway, since they believe God worked miracles at various points during history.
The multiverse: the fly in the Darwinian’s ointment
There are several flaws in Professor Coyne’s arguments, which I shall discuss shortly. But Coyne really gives the game away when he remarks in passing that “the laws of nature may vary among different universes if we have a multiverse.” For the multiverse is precisely what makes scientific inferences about the past, based on uniform laws, irrational. The reason is a very simple one: the number of possible universes in which the laws of Nature and the values of physical parameters vary over the course of time will infinitely exceed the number of possible universes in which the laws and physical parameters of Nature never vary, even in the slightest degree. And even if we restrict ourselves to the subset of possible universes in which life could exist, or to the still smaller subset of universes in which life actually appears and in which organisms are able to survive over long periods, we would still find that the number of these universes in which laws and physical parameters vary (either slightly, briefly or locally) infinitely exceeds the number of universes in which the laws and physical parameters never vary. Since (by the mediocrity principle) there is no reason to regard our own universe as exceptional, it is rational to conclude that the laws and physical parameters of Nature have varied in the past, in our universe. Since miracles only require variations which are infrequent, local and brief, it follows that there can be no scientific objection to the possibility of miracles, if we define these as events arising from singular variations in the laws and physical parameters of Nature.
It is important to keep in mind here that for Darwin and his contemporaries, any valid scientific explanation of a phenomenon had to be an explanation in terms of fixed and invariant laws. As Darwin wrote in his autobiography:
Everything in nature is the result of fixed laws.
(Barlow, Nora ed. 1958. The autobiography of Charles Darwin 1809-1882. With the original omissions restored. Edited and with appendix and notes by his grand-daughter Nora Barlow. London: Collins. Page 87. Available online here at Darwin Online.)
Why even Biblical creationism is more rational than Darwinian uniformitarianism, if you believe in a multiverse
It gets worse. One can argue that the number of possible universes whose histories conform to the (relatively modest) constraints of Biblical creationism will infinitely exceed the number of possible universes whose histories conform to the far more exacting constraints of uniformitarianism. For all that Biblical creationism requires us to hold is that on about 120-odd occasions in history, the laws and physical parameters of Nature were allowed to vary locally, for relatively brief periods, in a very specific way, which did not prove fatal for life on Earth. And that’s all. On other occasions, the laws and parameters may have either remained constant or varied slightly, within the restricted range imposed by the requirement that life on Earth continue to exist. By contrast, the demands of uniformitarianism are much more stringent: no variation in the laws and parameters is permitted to occur in even the tiniest nook or cranny of the universe we live in, over its entire history.
Here’s a simple illustration that will help readers to see why uniformitarianism is more restrictive than Biblical creationism. To simulate creationism, let’s consider the (infinite) number of curves that can be drawn on the x-y plane which go through a specific point that lies off the x-axis, corresponding to a specific miracle. Even if we add 120 more points lying off the x-axis (which represent all the miracles listed in the Bible), there is still an infinite number of curves that go through all of these points. And if we impose the additional restriction (corresponding to the requirements of life on Earth) that these curves have to stay very close to the x-axis (say, between the lines y = -1 and y = 1) for all values of x except those 120-odd points [and very short intervals on either side of these points], then we can still draw an infinite number of curves conforming to these requirements. Now consider the number of curves that can be drawn which go along the x-axis, never veering above or below it: only one. That’s uniformitarianism. In short: because multiverses allow laws to vary bizarrely on rare and singular occasions, and because not all such variations are fatal to life, we can conclude that a life-permitting universe is far more likely than not to experience anomalous events (which some might call miracles), and that a life-permitting universe in which Biblical miracles occur is still more likely than one in which the laws and physical parameters of Nature are always uniform. Thus Ken Ham’s belief that we live in in a universe where Biblical miracles occurred will still be more rational than the modern scientific belief that we live in a universe whose laws are space- and time-invariant, because Ham-type universes are more common in the multiverse than law-invariant universes. And since the argument for Darwinian evolution is based on the assumption that the laws and parameters of Nature do not vary, it follows that if we live in a multiverse, then our own universe is infinitely more likely to be one in which the miracles of the Bible occurred than a uniformitarian one in which life evolved in a Darwinian fashion.
Of course, an atheist could still retort that I’ve ignored the Biblical miracle of creation. In Ken Ham’s universe, the world and all of the species of living things arise within the space of just six 24-hour days, which is a fantastically improbable occurrence. What’s more, only a vanishingly small proportion of Ken Ham-style universes will contain a fossil record which fits the evolutionary account of life, or for that matter, living organisms whose genetic, anatomical, embryological and biogeographical properties accord with the striking predictions of Darwinism.
But Ham could reply that there will still be a number of possible universes in the multiverse, in which life pops into existence in the manner described in Genesis 1, and where living things just happen to exhibit the striking traits predicted by Darwinism, whereas there is (by definition) only ONE way for a given set of laws and parameters NOT to vary: namely, by remaining the same at every point in space and time. Putting it another way: the comparison we are making here is NOT one between Darwin’s theory and creationism, per se, but between uniformitarianism-plus-Darwinism with “singularism”-plus-Biblical literalism, where “singularism” refers to the hypothesis that the laws and physical parameters of Nature may undergo slight, short-lived or local fluctuations.
As we’ve seen, Professor Coyne argues that an evolutionary account of our origins is a far superior explanation to the creation story in Genesis, since Darwin’s theory of evolution makes very striking and amply confirmed predictions (e.g. about the whale fossils that scientists will discover), whereas Biblical creationism does not. In mathematical terms, the level of confirmational support which the fossil, genetic, embryological and biogeographical evidence provides for Darwinism (as against the rival hypothesis of creationism) is very, very high. Let us generously assume that Coyne is 100% right here – in other words, let’s ignore (for the moment) the difficulties relating to abiogenesis, the Cambrian explosion, irreducibly complex molecular machines, orphan genes and so on. The mathematical point that Coyne overlooks is that if a hypothesis is extremely unlikely to begin with (i.e. if it has a very low prior probability), then one should accept it only when the level of support for the hypothesis overwhelms its inherent improbability. The problem for Coyne is that the uniformitarian requirement that the laws and parameters of Nature are the same at every point in space and time – which is rather like hitting bull’s eyes again and again and again, for billions of years – is inherently so very unlikely, when compared to “singularism” (the hypothesis that the laws of Nature undergo slight, short-lived or local fluctuations) or for that matter, Biblical literalism (the narrower hypothesis that these exceptions occur in the manner described in the Bible), that even the high level of support that living things provide for Darwinism by conforming to its striking predictions is insufficient to overcome its inherent improbability as a uniformitarian theory.
Thus in a multiverse scenario, uniformitarianism becomes the albatross around the neck of Darwinism: no matter how many of Darwin’s predictions scientists manage to confirm, the sheer unlikelihood of the hypothesis that we live in a universe whose laws never vary renders Darwinism too unlikely a theory to warrant scientific consideration.
A response to some objections to my argument
In the argument I formulated above, I assumed that universes whose laws and physical parameters were absolutely invariant over space and time were extremely rare. But an atheistic physicist like Professor Sean Carroll of the California Institute of Technology might argue that universes whose laws and parameters fluctuated wildly would be unstable and short-lived, and that stabler universes whose laws and parameters never varied would tend to predominate in the multiverse as a whole, making uniformitarianism a much more reasonable assumption. This argument probably has some merit, if we consider wild, global fluctuations in laws and parameters. But I can see no reason why slight, short-lived or local fluctuations would be destabilizing for the universe in which they occurred. Given the vast number of ways in which laws and parameters can vary – even within narrow bounds – one would expect such universes to predominate over absolutely uniform ones.
A second objection is that in my illustration relating to curves on the x-y axis, I implicitly assumed that the laws and parameters of Nature were capable of varying in a continuous fashion, whereas in reality, these parameters are quantized and discontinuous. Hence one cannot argue that universes where the laws and parameters of Nature vary are infinitely more numerous than universes where they never vary. Maybe so; but they are still vastly more numerous, given that the quantum intervals we are speaking of are very, very small. For instance, a Planck length, which some physicists take to be the shortest possible length in our universe, is about 1.6×10^(-35) meters. All that my argument assumes is that universes where uniformitarianism holds are very uncommon, in the multiverse.
A third possible objection against my argument is that the constancy of the laws of Nature is a trivial consequence of the universe possessing a certain kind of symmetry, as Noether’s first theorem demonstrates. Each kind of symmetry entails its own conservation law. However, in a multiverse, the proportion of universes which are very slightly asymmetrical, and in which conservation laws don’t hold at all places and times, will surely vastly exceed the tiny proportion of universes that are perfectly symmetrical, so it seems to me that the appeal to Noether’s first theorem merely defers the question of why the laws and parameters of nature should be the same at all times and places.
A final objection that might be raised against my argument is that Darwinism is not, after all, tied to the unformitarian hypothesis that the universe’s laws and physical parameters are absolutely invariant over time. For living things could still evolve and survive in a world where slight variations in the laws and parameters of Nature occurred, and the number of universes in which life arose and evolved in a step-by-step fashion would vastly outnumber the miniscule fraction of universes in which life arose in a single step over a few days, making Darwinism a much more rational option than Ken Ham’s six-day creationism, as an account of origins. But the problem with this argument is that it concedes too much. All it would demonstrate is that life arose and evolved naturally. But Darwinian evolutionists are committed to a far more ambitious hypothesis: naturalism, which declares that miracles never occur at any time, anywhere in the universe. And the problem here is that if we define miracles as one-off, sharp variations (which may be local and/or very brief) in the laws and parameters of Nature, then even if we confine ourselves to the set of universes where life arose and evolved in a Darwinian fashion, we will still find that in most of these universes, miracles occur at some place and time. What this means is that you can be a Darwinian only if you are prepared to ditch naturalism – something which I don’t think too many Darwinists would be keen to do.
Some clarifications
Let me hasten to add that I am not for a moment suggesting that Ken Ham’s six-day creationism is correct. As I’ve declared many times, I believe in an old cosmos and in common descent, but I reject the hypothesis that life in all its complexity could have originated via the unguided processes of random variation and natural selection. Nor am I arguing that Ken Ham’s views are rational. The point I’m trying to make here is that if you happen to be a materialistic atheist who also believes in a multiverse – as nearly all scientific atheists do – then you can have no good epistemic grounds for rejecting Ken Ham’s Biblical creationism in favor of Darwinism. In fact, if you’re an atheist who believes in a multiverse, then Ken Ham’s Biblical creationism, silly as it may sound to some, is actually a more rational option than Darwinism. For the problem, as I’ve pointed out, is that Darwinism is built on the bedrock of uniformitarianism, which is an astronomically improbable hypothesis, and there are many more life-containing universes in the multiverse where Ken Ham’s Biblical creationism holds true and where (by sheer coincidence) the striking predictions of Darwinism also happen to hold true, than there are universes where uniformitarianism holds true.
What this means is that if you want to argue against Ken Ham’s six-day creationism, then you have two options: you can either ditch the multiverse – a risky proposition for an atheist, given the extensive evidence of cosmological fine-tuning and the astronomical odds against life originating from non-living matter, as calculated by evolutionary biologist Dr. Eugene Koonin – or you can argue against six-day creationism from a theistic standpoint. A theist could argue that we should believe that the laws and physical parameters of Nature hold constant, because God would want it that way. In the nineteenth century, Reverend Baden Powell argued on theological grounds that the laws of Nature were edicts issued by God at the time of Creation, and that any violation of these laws would constitute a breach of promise on God’s part – something which God cannot do. Alternatively, a theist might argue that the absolute constancy of the laws and physical parameters of Nature over time is a powerful sign that they were designed by God, since this invariance over space and time would be extremely unlikely if our universe was but one of many universes in an infinite multiverse. However, a theist might also allow for the possibility of localized exceptions to these invariant laws and parameters, which we call miracles: after all, God is free to break His own rules if He has special reasons for doing so. On such a theistic account, belief in miracles would be epistemically warranted, if we have sufficient testimonial evidence for their occurrence. However, a theist would be entitled to reject claims for miracles which force us to pile one ad hoc assumption on top of another, in order to explain their occurrence. For example, one reason why many Christian theists today reject the idea of a global Deluge in the past is that one would need to posit an additional miracle in order to explain where all the heat released by a global Deluge would have gone, even though no such miracle is recorded or even hinted at in Scripture.
Observational and historical sciences: is there a distinction between them?
I’d now like to turn to Coyne’s claim that “there is no distinction between historical science and real-time experimental science: both are based on observation, prediction, and testability.” I have to say that this statement is simply wrong. That doesn’t mean I agree with Ham’s characterization of the historical and experimental sciences: Coyne is perfectly right, for instance, when he asserts that the historical sciences make predictions that can be tested. Nevertheless, there are important differences between the historical and experimental sciences, and when biologists like Professor P.Z. Myers object to creationists making a “bizarre distinction between observational and historical science,” they are simply displaying their ignorance.
I refer Coyne and Myers to an article by Carol Cleland titled Historical science, experimental science, and the scientific method (Geology; November 2001; v. 29; no. 11; p. 987–990). Cleland begins by criticizing former Nature editor Henry Gee for his dismissive assertion that all hypotheses about the remote past are unscientific, since “they can never be tested by experiment, and so they are unscientific… No science can ever be historical” (In search of deep time, New York, 1997; The Free Press, pp. 5,8). Cleland also criticizes “physicists and chemists who attack the scientific status of neo-Darwinian evolution” on the same grounds. On this point, I think she is correct. Nevertheless, Cleland insists that there is a fundamental difference between the historical and experimental sciences, in their methodologies, and here she agrees with Gee:
Although the idea that all good scientists employ a single method for testing hypotheses is popular, an inspection of the practices of historical scientists and experimental scientists reveals substantial differences. Classical experimental research involves making predictions and testing them, ideally in controlled laboratory settings. In contrast, historical research involves explaining observable phenomena in terms of unobservable causes that cannot be fully replicated in a laboratory setting…
In summary, Gee (1999) was correct about there being fundamental differences in the methodology used by historical and experimental scientists. Experimental scientists focus on a single (sometimes complex) hypothesis, and the main research activity consists in repeatedly bringing about the test conditions specified by the hypothesis, and controlling for extraneous factors that might produce false positives and false negatives. Historical scientists, in contrast, usually concentrate on formulating multiple competing hypotheses about particular past events. Their main research efforts are directed at searching for a smoking gun, a trace that sets apart one hypothesis as providing a better causal explanation (for the observed traces) than do the others. These differences in methodology do not, however, support the claim that historical science is methodologically inferior, because they reflect an objective difference in the evidential relations at the disposal of his-
torical and experimental researchers for evaluating their hypotheses.
In the passage above, Cleland refers to cases where historical scientists discover a “smoking gun”: “a trace that sets apart one hypothesis as providing a better causal explanation (for the observed traces) than do the others.” The example she discusses is the discovery of extensive deposits of iridium and shocked quartz in the Cretaceous-Tertiary boundary, coupled with the discovery that the demise of the dinosaurs was a sudden one. Can smoking guns redeem the case for Darwinian evolution? Not if we live in a multiverse, for the reason that I discussed earlier: although creationism fails to make such striking predictions, the number of possible universes whose histories conform to the (relatively modest) constraints of creationism will infinitely exceed the number of possible universes whose histories conform to the far more exacting constraints of uniformitarianism.
Would Ken Ham’s skepticism invalidate the historical sciences?
In his post, Professor Jerry Coyne argues that Ken Ham’s assertion that the historical sciences are open to doubt because they deal with events that can’t be observed, would invalidate not only evolution but also cosmology, geology and even archaeology. I imagine Ham would probably agree that the sciences of cosmology and geology, which deal with events occurring in deep time, are indeed provisional. However, it does not follow from Ham’s logic that we should also doubt the findings of archaeology, let alone the conclusions that historians have arrived at about the past, from studying ancient records. With regard to archaeology, Ham would obviously contest the dating of certain artifacts (such as Stone Age tools which have been dated back to 2.6 million years ago), but he could argue that their specified complexity leaves no doubt that they were designed by someone. Regarding history, Ham would presumably argue that what we are dealing with here is the testimony of eyewitnesses (or second-hand reports), written down in the language of their day. [The hyper-skeptical hypothesis that the testimonies might have been forged by a capricious or mischievous God can be dismissed, as theists are not committed to the view that the universe is the product of God’s whim; what they assert is that it is the product of His (non-arbitrary) Will. See my discussion of the laws of Nature below.] The only questions that need to be answered about these testimonies are: were the alleged eyewitnesses reliable observers, and were they telling the truth? These uncertainties are fundamentally different in kind from the physical uncertainties regarding whether the laws and parameters of the cosmos were the same in the past as they are today. In short: to cast doubt on the findings of cosmology and geology is not the same as casting doubt on the findings of historians.
Is God a poor explanation for the laws of Nature?
Professor Coyne also argues that “God made them that way” is a very poor explanation for why the laws of Nature hold constant. But here he is construing laws as mere whims of the Almighty. That is not the view that I am espousing here. In order to see why any scientific account of laws is too thin to provide a warrant for induction about future events, consider the following question: are the laws of Nature merely descriptive statements about how the universe happens to work, or are they prescriptive statements about how things should behave? The problem here is that as Hume observed, one cannot derive an “ought” from an “is”: hence if laws are mere descriptions of how Nature works, they cannot tell scientists what they should expect to observe in the future. But if, on the other hand, we say that laws are prescriptions about how things should behave, then we have implicitly acknowledged the existence of a Cosmic Prescriber. (After all, things cannot tell themselves how they ought to act.) In other words, the prescriptive view of laws – which is the only one that can ground inductive inferences – implies the existence of a Divine Lawmaker.
On the view I am proposing, laws are no mere whims, but prescriptions which define the very character of the various kinds of things we observe in Nature. And since they characterize the kinds of objects we find in Nature, they cannot be changed without destroying those very objects. That of course raises the question of how miracles could possibly occur – a question which the philosopher Alfred Freddoso answers here. In a nutshell: Freddoso is a concurrentist, who believes that whenever objects produce their effects, they can only do so with the concurrent assistance of God; hence if God withholds His assistance, the object will not produce its customary effect. (Fire, for instance, will not burn Shadrach sitting in the fiery furnace unless God co-operates in His usual fashion.) Hence on extraordinary occasions it is possible for God to prevent things from producing their usual effects without destroying their character – simply by withholding His customary co-operation with natural agents.
Summary
I conclude, then, that Professor Coyne’s attack on Ken Ham relies on specious arguments, and that atheists are in no position to criticize Ham as irrational. Pot, kettle, anyone?